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        <h2>Table of Contents</h2>
        <ul>
<li><a href="#tty_tty">TTY</a><ul>
<li><a href="#tty_class_tty_readstream">Class: tty.ReadStream</a><ul>
<li><a href="#tty_readstream_israw">readStream.isRaw</a></li>
<li><a href="#tty_readstream_setrawmode_mode">readStream.setRawMode(mode)</a></li>
</ul>
</li>
<li><a href="#tty_class_tty_writestream">Class: tty.WriteStream</a><ul>
<li><a href="#tty_event_resize">Event: &#39;resize&#39;</a></li>
<li><a href="#tty_writestream_columns">writeStream.columns</a></li>
<li><a href="#tty_writestream_rows">writeStream.rows</a></li>
</ul>
</li>
<li><a href="#tty_tty_isatty_fd">tty.isatty(fd)</a></li>
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        <h1>TTY<span><a class="mark" href="#tty_tty" id="tty_tty">#</a></span></h1>
<pre class="api_stability api_stability_2">Stability: 2 - Stable</pre><p>The <code>tty</code> module provides the <code>tty.ReadStream</code> and <code>tty.WriteStream</code> classes.
In most cases, it will not be necessary or possible to use this module directly.
However, it can be accessed using:</p>
<pre><code class="lang-js">const tty = require(&#39;tty&#39;);
</code></pre>
<p>When Node.js detects that it is being run inside a text terminal (&quot;TTY&quot;)
context, the <code>process.stdin</code> will, by default, be initialized as an instance of
<code>tty.ReadStream</code> and both <code>process.stdout</code> and <code>process.stderr</code> will, by
default be instances of <code>tty.WriteStream</code>. The preferred method of determining
whether Node.js is being run within a TTY context is to check that the value of
the <code>process.stdout.isTTY</code> property is <code>true</code>:</p>
<pre><code class="lang-sh">$ node -p -e &quot;Boolean(process.stdout.isTTY)&quot;
true
$ node -p -e &quot;Boolean(process.stdout.isTTY)&quot; | cat
false
</code></pre>
<p>In most cases, there should be little to no reason for an application to
create instances of the <code>tty.ReadStream</code> and <code>tty.WriteStream</code> classes.</p>
<h2>Class: tty.ReadStream<span><a class="mark" href="#tty_class_tty_readstream" id="tty_class_tty_readstream">#</a></span></h2>
<div class="api_metadata">
<span>Added in: v0.5.8</span>
</div><p>The <code>tty.ReadStream</code> class is a subclass of <code>net.Socket</code> that represents the
readable side of a TTY. In normal circumstances <code>process.stdin</code> will be the
only <code>tty.ReadStream</code> instance in a Node.js process and there should be no
reason to create additional instances.</p>
<h3>readStream.isRaw<span><a class="mark" href="#tty_readstream_israw" id="tty_readstream_israw">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.7.7</span>
</div><p>A <code>boolean</code> that is <code>true</code> if the TTY is currently configured to operate as a
raw device. Defaults to <code>false</code>.</p>
<h3>readStream.setRawMode(mode)<span><a class="mark" href="#tty_readstream_setrawmode_mode" id="tty_readstream_setrawmode_mode">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.7.7</span>
</div><ul>
<li><code>mode</code> <span class="type">&lt;boolean&gt;</span> If <code>true</code>, configures the <code>tty.ReadStream</code> to operate as a
raw device. If <code>false</code>, configures the <code>tty.ReadStream</code> to operate in its
default mode. The <code>readStream.isRaw</code> property will be set to the resulting
mode.</li>
</ul>
<h2>Class: tty.WriteStream<span><a class="mark" href="#tty_class_tty_writestream" id="tty_class_tty_writestream">#</a></span></h2>
<div class="api_metadata">
<span>Added in: v0.5.8</span>
</div><p>The <code>tty.WriteStream</code> class is a subclass of <code>net.Socket</code> that represents the
writable side of a TTY. In normal circumstances, <code>process.stdout</code> and
<code>process.stderr</code> will be the only <code>tty.WriteStream</code> instances created for a
Node.js process and there should be no reason to create additional instances.</p>
<h3>Event: &#39;resize&#39;<span><a class="mark" href="#tty_event_resize" id="tty_event_resize">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.7.7</span>
</div><p>The <code>&#39;resize&#39;</code> event is emitted whenever either of the <code>writeStream.columns</code>
or <code>writeStream.rows</code> properties have changed. No arguments are passed to the
listener callback when called.</p>
<pre><code class="lang-js">process.stdout.on(&#39;resize&#39;, () =&gt; {
  console.log(&#39;screen size has changed!&#39;);
  console.log(`${process.stdout.columns}x${process.stdout.rows}`);
});
</code></pre>
<h3>writeStream.columns<span><a class="mark" href="#tty_writestream_columns" id="tty_writestream_columns">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.7.7</span>
</div><p>A <code>number</code> specifying the number of columns the TTY currently has. This property
is updated whenever the <code>&#39;resize&#39;</code> event is emitted.</p>
<h3>writeStream.rows<span><a class="mark" href="#tty_writestream_rows" id="tty_writestream_rows">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.7.7</span>
</div><p>A <code>number</code> specifying the number of rows the TTY currently has. This property
is updated whenever the <code>&#39;resize&#39;</code> event is emitted.</p>
<h2>tty.isatty(fd)<span><a class="mark" href="#tty_tty_isatty_fd" id="tty_tty_isatty_fd">#</a></span></h2>
<div class="api_metadata">
<span>Added in: v0.5.8</span>
</div><ul>
<li><code>fd</code> <span class="type">&lt;number&gt;</span> A numeric file descriptor</li>
</ul>
<p>The <code>tty.isatty()</code> method returns <code>true</code> if the given <code>fd</code> is associated with
a TTY and <code>false</code> if is not.</p>

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